Method of and means for preserving wooden piles



March 26, 1940. T, H, HANSEN 2,195,275

mamon or mm ums ron rnssnnvrue woonnu PILES Filcd Nov. 5. 1938 INVENTOR. IIe/WAM HAMM/J ATTORNEY.

Patented Mar. 26, 1940 METHOD 0F AND MEANS FOR PBESERVING WOODEN PILES Thon-wald H. Hansen, Brighton, Trinidad, Brltis West Indies Application November 3, 1938, Serial No. 238,522 l 13 Claims.

structural members, such as wooden piles, telephone and telegraph poles, and the like, from destruction by erosion due to various factors.'

Erosion of piles and poles takes place, for example, bythe mechanical action of waves, by the destructive action of marine and other life, such as the toredo, termites, and the like. Erosion also takes place by reason of collision due to vessels, vehicles, ice, driftwood, and the like. In order to prevent such destruction, which usually takes place in a relatively narrow section of the length of the pile or pole, various means have heretofore been proposed. It has been quite common to impregnate piles with creosote or the like, which prevents the action of marine and other life. However, such protection is only temporary, as the creosote after a relatively short time, seeps out of the piles and allows the action of the marine life to take place. In certain localities, particularly in the tropics and sub-tropics, the erosion is so rapid that the ordinary pile used for pier construction becomes entirely eaten away in a space of one to seven years. y

It has been proposed to continue the vprotection of the creosote or the like by various means. One proposed `method has been to surround the pile with a oat having an internal chamber containing a relatively large supply of creosote, with brushes to confine the creosote within the chamber. The oat was so mounted as to move up and down with the tide, and thus providea coating of creosote on the outside of the pile. However, this was not eiective in that the exposure of the creosoted surface to the action of the water resulted in the same being almost immediately removed from the pile, and thus the protection was quickly lost. Furthermore, this did not result in vany protection against mechanical erosion, as this was not diminished at all. Furthermore, this type of protection was quite` expensive to install and was almost impossible to maintain in working condition, principally because of the fact that in a. collision with a floating object. the float member was'so distorted as to render` it incapable of movement. r

Another system previously proposed and adapted more particularly to telephone and telegraph poles consisted in molding around the pole a casing of concrete and the like havingV a chamber formed in the upper part of said'casing. Said chamber was illled with suitable preservative ma# This method was quite expensive, in`

(Cl. (il-54) operation was necessarily slow and long drawn out, requiring specially skilled labor.

The present invention is intended and adapted to overcome the disadvantages of prior methods and to provide protection for piles and the like which is readily installed at a low cost, which 1s extremely effective in its action, which preserves the piles and the like for very long periods of time against both mechanical erosion and destruction by marine and other life, and which requires but very little maintenance in order to keep the same in working condition.

In practicing my invention, I provide at an upper portion of the pile or the like a chamber for liquid preservative, such as creosote, said chamber being formed within the outer layers of the pile. This may be accomplished in a number of ways, the intention being to form a reservoir within the outer annual rings of the wood. Usually, the reservoir `is formed within one inch of the outer surface of the pile. There is also provided at a certain Iarea below said reservoir a jacket of "suitable ymaterial, said jacket being placed over that portion of the pile which is subjected to erosion. In its operation, my invention contemplates that the liquid preservative in the reservoir travels within the pile itself and between the adjacent outer annual rings down to the portion to be protected, which is between the high water mark and the mud-line. Insaid portion the preservative spreads and lls the outer shell of the pile, while the jacket connes the preservative at the point of erosion to avoid any leakage. In order to replenish the supply of preservative, it is merely necessary at relatively long intervals to introduce into the reservoir a small amount thereof. The jacket and reservoir may be combined as by bringing the jacket up or the reservoir down.

In the accompanying drawing, constituting a part hereof, and in which like reference characters indicate like parts,

Fig. 1 is a front elevational View of a bent constituting asection of a pier and embodying the improvements of the present` invention, some parts being shown in section;

Fig. 2 is a fragmentary elevational view of the top of a pile, showing a modification of the reservoir for the liquid preservative;

Fig. 3 is a top plan view thereof;

Fig. 4 is a fragmentary side elevationalview of a pile showing a still further modified reservoir;

Fig. 5 is a top plan view thereof, and

Fig. 6 is an enlarged fragmentary view showing the top of the concrete jacket.

Each bent or section of a typical pier consists of a series of piles l, 2 and 3, in substantially vertical position and joined by beams 4 and having bracing members 5 suitably secured thereto as is well known. A iloor 6 is provided 4on top ofthe construction and usually at4 the side are a series of piles 1 protected by horizontal fender beams I. 'I'he piles are usually driven down below the mud-line 9 to` a variable distance, depending upon the conditions of the sub-soil and the service to which the structure is to be put.

In accordance with the present invention, there is provided at the upper portion of the piles a reservoir which may be formed by cutting an annular groove Il, extending diagonally downward and inward, as shown in' Fig. 1, into the outer annual rings of the wood. A metal leatproof band II is secured thereto by a series of nails l2 along the upper and lower edges thereof and an opening I3 is provided near the top of the band II whereby additional preservative may be introduced. There may be some weakening of the pile by reason .of the removal of wood therefrom to form the groove or reservoir III, but this is adequately compensated for by the additional strength provided by the metal band I I, which may be made of such material and of such strength as to give the entire structure its original strength. The liquid preservative, which may be ordinary cresote, travels down through the outer rings ofthe pile, as shown at I4, and past the space covered by the jacket I5.

Said jacket covers the portion of the pile between the low water mark I6 and the high water mark Il, the jacket extending upwardly above the high water line and downwardly below the low water line, since substantially all of the erosion to which the pile is subjected is between these points. The jacket I 5 is made of concrete and may be provided with reinforcing as wire mesh I8. At the top of jacket I5 is a metal band I9 of suitable material and held in place by nails 20. Its upper edge is above the top of jacket I5 and it extends, as shown in Fig. 1, to a short distance below the top of said jacket. The purpose ol this is to prevent the liquid preservative flowing down through I4 to emerge at the top of ljacket I5 and thus not only be ineiective, as

it would be rapidly washed away, but also to prevent the same from coming in contact with concrete and avoiding the destruction of the concrete by the oily material.

It is not necessary that the jacket I5 be of concrete, and in some instances, especially where it would be subjected to collision, it is preferable to have a metal jacket. Therefore, it is preferre, as shown on fender pile 1 and the adjacent pile I, to surround the pile by a metal jacket 2I suitably held in place, as by nails 22.

By the structure above described it has been found that illling the reservoir `III with approximately one-half to one pint of creosote is suilicient to give full and adequate protection against all forms of destruction for a substantial period, which varies with the local conditions. It

-has been found in actual practice that in many cases one illling per year is sumcient, whereas' it may be, under the most strenuous conditions, necessary to retlll the reservoir as much as once per month, depending upon the conditions aiiecting the attack by marine borers, climate, character of water, and the like. It has been found that on the average, refilling every three or four months is suillcient for complete protection. This is accomplished very readily by injecting into opening I3 by means of a suitable pump or otherwise, the desired amount of liquid, causing the preservative to ow around and down one inch of the circumference of the pile. Thereby the pressure on the liquid may be adjusted to Rive the desired flow of said liquid; Pressure is particularly desirable when untreated piles are provided with the present `improvements to insure penetration of the liquid through the cells of the wood.

In some cases, and particularly where there are clusters of piles such as dolphins, the annular groove II cannot be conveniently made. In such case I may provide a structure such as shown in Figs. 2 and 3. At the top 23 of the pile and adjacent the outer edge thereof, there are formed of the wood extending downwardly and diagonally as shown at 25. This forms a series oi' reservoirs, each holding a relatively small amount of preservative, and because of the convenience of location theymay be easily lled. While ordinarily it is unnecessary to cover the openings 2l, under. some conditions it may be advisable to furnish the same with plugs or the like.

In Figs. 4 and 5 I have shown a still further modication of the reservoir construction. In-

stead of forming the openings at the top of the pile, it may be formed at any intermediate point, the holes being bored around the circumference as shown at 26 and extending diagonally downward in a more or less tangential direction, as best shown in Fig. 5. By a structure of this kind, even though a part of the periphery of the pile is inaccessible, the direction in which the holes are bored is such as to provide a supply of preservative, along practically the entire circumference of the pile.

The height at whichthe reservoir II) or the holes 24 or 28 are placed may be varied with conditions. Practical experience has shown that where the reservoir is placed as much as seven feet above the' top of the section to be protected, the ilow of liquid preservative is rapid and'complete and unobstructed'. The reservoir may be placed at even a greater height or at any lesser height desired, as the preservative seeps freely downwardly through the jacketed space and the jacket adequatelyand completely prevents leakage. If there is some slight leakage around the band II, it assists in the preservation of the pile, in that it may form a creosote outer coating above the water level, so that there is no removal of such creosote by wave action.

Although I have described my invention with particular emphasis upon wooden piles forming part of a pier construction, it will be quite obvious that this type of protection is not at all limited to piers, although it has been found very valuable therein. lThe invention is y equally .a series of holes 24 in the outer annular rings adapted for the protection of telephone and telegraph poles and the like, either on water or on land, as in the latter case erosion takes place by reason of land borers and the like, andy also by mechanical action. In the case of telephone poles, it is possible to place the reservoirat a suiiicient height so that it cannot be tampered with `by an individual, and the jacket may be rather short and be placed, say, over an area from six inches below the ground level to about one foot above said level. The replenishing oi' the reservoir with preservative need be only at infrequent intervals, say once or twice per year, and may be conveniently accomplished by suitable apparatus. I

'Ihe various-materials used in practicing the present invention may be of any desired or convenient type, as for example, the bands Il, II and 2 I may be made of ordinary sheet steel, although for long life other materials are preferable, as for instance, corrosion resistant alloys, such as stainless steel, Muntz metal, copper and various others which are known to be resistant to marine borers and to the corrosive effects of atmospheric conditions. When properly protected by the present method, piles which normally would be entirely eroded so as to require replacement in about six or seven years, have been so fully protected by the present invention that after seven years the piles were in as good condition as the day the protection was applied. It is considered that by the present invention it is possible to take piles which have been eroded to a point where their usefulness is over and, without removing them from the structures in which they are found, to protect them and to render the life thereof as much as fty years.

It will be appreciated that various other,

changes and modifications in the details of the operation of the present invention may be made within the scope thereof, and the invention is not to be limited except by the character of the claims appended hereto. For instance, the reservoir may be formed in the jacketed portion and a pipe led therefrom to a convenient'point for refilling said reservoir.

What I claim is:

1. A method of treating wooden piles whichv comprises forming a reservoir within the upper part of a pile adjacent to the outer surface thereof, placing a liquid wood preservative in said reservoir, enclosing a. lower portion of saidplle subject to erosion in a fitted jacket, whereby preservative flows downwardly through the outer annual rings and thru said enclosed portion.

2. A method of treating wooden piles which comprises forming a reservoir within the upper part of a pile adjacent to the outer surface thereof, placing a liquid wood preservative in said reservoir, enclosing a lower portion of said pile subject to erosion in a fitted jacket, said jacket being of concrete and having a metal band closely surrounding said pile at the upper end of said jacket, whereby preservative flows downwardly through the outer annual rings and thru said enclosed portion.

3. A method of treating wooden piles which comprises forming a reservoir within the upper part of a pile adjacent to the outer surface thereof by boring a plurality of holes extending diagonally downward and in the outer annual rings, placing a liquid wood preservative in said reservoir, enclosing a lower portion of said pile subject to erosion in a tted jacket, whereby preservative flows downwardly through the outer annual rings and thru said enclosed portion.

4. A method of treating wooden piles which comprises forming a reservoir within the upper part of a pile adjacent to the outer surface thereof by cutting an annular groove into the outer annual rings and covering the same with a band, placing a liquid wood preservative in said reservoir, enclosing a lower portion of said pile subject to erosion in a fitted jacket, whereby preservative flows downwardly through the outer annual rings and thru said enclosed portion.

5. Means for treating wooden piles comprising -a reservoir containing liquid preservative within the upper .part of a pile adjacent the outer annual rings thereof, a jacket enclosing a lower portion thereof to be protected, said means causing preservative to ow downwardly thru said jacketed portion.

6. Means for treating wooden piles comprising a reservoir containing liquid preservative within the upper part of a pile adjacent the outer annual rings thereof, said reservoir being annular, a jacket enclosing a lower portion thereof to be protected, said means causing preservative to flow downwardly thru said jacketed portion.

7. Means for treating wooden piles comprising a reservoir containing liquid preservative within the upper part of a pile adjacent the outer annual rings thereof, said reservoir being annular and having a cover thereover, a jacket enclosing a lower portion thereof to be protected, said means causing preservative to flow downwardly thru said jacketed portion.

8. Means for treating wooden piles comprising a reservoir containing liquid preservative within the upper part of a pile adjacent the outer annual rings thereof, said reservoir including a plurality of downwardly extending openings spaced about the periphery of said pile, a jacket enclosing a lower portion thereof to be protected, said means causing preservative to flow downwardly thru said jacketed portion.

9. Means for treating wooden piles comprising a reservoir containing liquid preservative within the upper part of a pile adjacent the outer annual rings thereof, a concrete jacket enclosing a lower portion thereof to be protected, said means causing preservative to flow downwardly thru said jacketed portion.

10. Means for treating wooden piles comprising a reservoir containing liquid preservative within the upper part of a pile adjacent the outer annual rings thereof, a concrete jacket enclosing a lower portion thereof to be protected, said means causing preservative to ow downwardly thru said jacketed portion, and a metal band closely surrounding said pile at the upper end of said jacket to avoid leakage of preservative onto said concrete.

l1. Means for treating wooden piles comprising a reservoir containing liquid preservative within the upper part of a pile adjacent the outer annual rings thereof, a jacket enclosing a lower portion thereof to be protected, means for refilling said reservoir, said first means causing preservative to flow downwardly thru said jacketed portion.

12. Means'for treating wooden piles comprising a reservoir containing liquid preservative within the upper part of a pile adjacent the outer annual rings thereof, said reservoir being annular, a jacket enclosing a lower portion thereof to be protected, said means causing preservative to flow downwardly thru said jacketed portion. the lower surface of said reservoir being in a plane substantially at right angles to said rings.

13. A method of treating wooden piles which comprises forming a reservoir within the upper part of a pile adjacent to the outer surface thereof, placing a liquid wood preservative in said reservoir, enclosing a lower portion of said pile subject to erosion in a fitted jacket, whereby .v 

